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This study reports the recognition of Vitis adenoclada Hand.-Mazz. from southern China. The species was not recognized in the Flora Reipublicae Ropularis Sinicicae and Flora of China treatments. Recent field studies and examination of herbarium collections including the type material suggest that Vitis adenoclada is morphologically similar to V. heyneana, in their densely arachnoid tomentose abaxial leaves, yet it can be easily distinguished from the latter by its red-purple glandular hairs on the young branches (vs. glandular hairs absent in V. heyneana) and inflorescences usually subtended by a tendril at the base (vs. only occasionally with a tendril in V. heyneana). Vitis adenoclada may be a species of hybrid origin, with the highly tomentose Vitis heyneana as one of the parental species, and likely the glandular-hair bearing V. davidii as the other parental species. Vitis adenoclada is recorded from southern China in Guangdong, Guangxi, Guizhou, Hunan and Zhejiang provinces.

Mafic lava is generally used to study the oxygen fugacity of lithospheric mantle. However, some studies confirmed that the high oxygen fugacity of mafic lava from lithospheric mantle may be result of auto-oxidation during the late magma evolution. Whether mafic lava reflects the oxygen fugacity of source area remains controversial. The major and trace element compositions of biotite, amphibole, and plagioclase as well as the Sr isotopes of plagioclase were in-situ examined aim to evaluate the variation in oxygen fugacity of mafic magma during transportation from depth to current location. Mineralogical characteristics show that the dikes originate from an enriched lithospheric mantle source and experienced very little or no crustal contamination during the magma transfer process. Clinopyroxene, plagioclase, Al-rich amphibole, biotite, and Mg-rich amphibole crystallized successively as the depth of magma reduced from 75.9 to 0.8 km. Fayalite-magnetite-quartz (△FMQ) and Ni-NiO (△NNO) are used as reference oxygen fugacity buffers in this study. The average oxygen fugacity of mafic magma gradually increases from △NNO-1.50 (lithospheric mantle source) to △NNO + 2.74 (near the surface) during magma evolution. Calculation results from clinopyroxene, amphibole and biotite show that the oxygen fugacity of magma increases during fractionation of clinopyroxene, plagioclase, amphibole, and biotite. However, the above fractionation cannot generate such a wide variation in oxygen fugacity. Moreover, it is not caused by degassing in terms of the low carbonate mineral content and increasing S6+/Stot ratios during fractionation. Previous studies have shown a rapid cooling and a high H2O content of the Jiaodong mafic magma. Combine with the garnet-spinel transition zone of mantle lithosphere and magnetite observed in petrography, we tend to propose that the variation in oxygen fugacity of mafic magma were caused by magnetite-spinel fractional crystallization at depth. Low-pressure metamorphic amphibole and the country rocks of Late Mesozoic monzodiorite, which has a much higher oxygen fugacity than the stable range of magnetite-spinel, indicated that the secondary alteration in last stage of magma evolution may cause additional variation in oxygen fugacity. In that case, mafic lava cannot be used to determine the oxygen fugacity of source rock.

Puccinia striiformis Westend. f. sp. tritici Erikss. (Pst) infects wheat and causes stripe rust. The rust is heteroecious with wheat as the primary uredinial and telial host and barberry (Berberis spp.) as the alternate pycnial and aecial host. More than 40 Berberis species have been identified as alternate hosts for Pst, and most of these are Chinese Berberis species. However, little is known about Berberis species or their geographic distributions in the Yunnan-Guizhou plateau in southwestern China. The Yunnan-Guizhou plateau is considered to be an important and relatively independent region for the evolution of the wheat stripe rust pathogen in China because the entire disease cycle can be completed within the region. In this study, we conducted a survey of barberry plants in the Yunnan-Guizhou plateau and identified the eight Pst-susceptible Berberis species under controlled conditions, including B. julianae, B. tsienii, B. veitchii, B. wilsonae, B. wilsonae var. guhtzunica, B. franchetiana, B. lepidifolia and B. pruinosa. These species are reported here for the first time to serve as alternate hosts for the wheat stripe rust pathogen under controlled conditions.

The change in the electrical properties of 4H-SiC Schottky barrier diodes (SBDs) irradiated by 6 MeV Au ions at low temperature (LT) is investigated. The SBDs are characterized by current–voltage (I-V) and capacitance–voltage (C-V). The SRIM software is used to calculate the Au ion transportation process. The experimental results indicate that the ideality factor (n) and the reverse leakage current (IR) increase, and Schottky barrier height (SBH) decreases with the increase in fluence. It is found that series resistance (RS) and effective impurity concentration (ND) are recovered at 5 × 1015 ions/cm2. Calculation results show that the mental layer can prevent most of the Au ions, while the secondary particles will enter the SiC layer. Therefore, these results demonstrate that the secondary particles induce many defects at the metal-SiC interface and the SiC epitaxial layer after LT heavy ion (HI) irradiation.

A multiepi (ME) superjunction (SJ) MOSFET with a lightly-doped MOS-channel diode (MCD) is studied by TCAD simulations. When the p-pillar is formed by the ME process, the resistance of the p-pillar can be much higher than that of a uniformly doped p-pillar, which helps to suppress reverse recovery oscillations of the body diode. Besides, by introducing the lightly doped MCD, electrons can easily flow from the n-pillar into the source contact when the body diode is in the ON-state. Thus, the hole injection efficiency of the body diode can be lowered to reduce reverse recovery charge ( ${Q}_{rr}$ ) and further suppress reverse recovery oscillations. Simulation results show that the proposed SJ MOSFET is able to obtain a 64% lower ${Q}_{rr}$ and much lower reverse recovery oscillations than the conventional SJ MOSFET with a uniformly doped p-pillar.

In this paper, we construct a class of new modules for the quantum group U q ⁢ ( s ⁢ l 2 ) U_{q}(\mathfrak{sl}_{2}) which are free of rank 1 when restricted to C ⁢ [ K ± 1 ] \mathbb{C}[K^{\pm 1}] . The irreducibility of these modules and submodule structure for reducible ones are determined. It is proved that any C ⁢ [ K ± 1 ] \mathbb{C}[K^{\pm 1}] -free U q ⁢ ( s ⁢ l 2 ) U_{q}(\mathfrak{sl}_{2}) -module of rank 1 is isomorphic to one of the modules we constructed, and their isomorphism classes are obtained. We also investigate the tensor products of the C ⁢ [ K ± 1 ] \mathbb{C}[K^{\pm 1}] -free modules with finite-dimensional simple modules over U q ⁢ ( s ⁢ l 2 ) U_{q}(\mathfrak{sl}_{2}) , and for the generic cases, we obtain direct sum decomposition formulas for them, which are similar to the well-known Clebsch–Gordan formula for tensor products between finite-dimensional weight modules over U q ⁢ ( s ⁢ l 2 ) U_{q}(\mathfrak{sl}_{2}) .

The function of a commercial Schottky Barrier Diode (SBD) based on 4H-SiC in an environment of extreme temperature and radiation was assessed. The capacitance-voltage (C-V) and current-voltage (I-V) characteristics of the devices were measured by heavy ions (HIs) irradiation at 3 different fluences and 15 different nodes of temperature. From these measurements, the effective carrier concentration (ND), reverse current (IR), series resistance (RS), ideal factor (n), and Schottky barrier height (SBH) were calculated and analyzed. Obvious increases of ND and IR were found and some changes of the electronic characteristics with temperature were enhanced by HIs. After the highest fluence of irradiation, the IR at low temperature (20 K) was even larger than the IR at room temperature, which was subjected to lower fluence of irradiation, suggesting risks for aerospace applications. These changes were attributed to defects both at the interface and in the body-substrate induced by irradiation.

To deeply understand and even describe the evolutions of the low-energy twin boundary density (BLD∑3n) in a thermal-plastic deformation process, an improved twin density model as a function of average grain size and stored energy is developed. For Nimonic 80A superalloy, the model is solved based on the EBSD statistical results of grain size and BLD∑3n in the specimens compressed at temperatures of 1273–1423 K and strain rates of 0.001–10 s–1. The corresponding relationships of BLD∑3n with stored energy and grain size varying with temperature and strain rate are clarified by the superimposed contour plot maps. It is summarized that BLD∑3n increases with increasing stored energy and decreasing grain size, and higher BLD∑3n with finer grains corresponds with lower temperatures and higher strain rates. Such relationships are described by the improved twin density model, and the prediction tolerance of the solved model is limited in 2.8%.

Human drivers can have diverse car-following behaviors when interacting with connected and automated vehicles (CAVs) and other human-driven vehicles in mixed traffic where many human-driven vehicles and a limited number of CAVs frequently interact and share the road. In this study, Inverse Reinforcement Learning (IRL) is used to model unique car-following behaviors of different human drivers when interacting with the CAV and another human-driven vehicle by using their driving demonstrations collected from in-field driving tests. The learned driver behavior model is shown that the personalized driving behaviors accurately and consistently can be characterized when following the different types of preceding vehicles in a variety of traffic situations. Furthermore, the energy efficiency of different human-driven vehicles when interacting with the CAV and the human-driven vehicle is investigated with the heterogeneous characteristics of drivers’ behaviors, considering driving behaviors have significant influences on vehicle fuel economy. A detailed analysis reveals the significant fuel-saving benefits of the CAV to the following human-driven vehicles during the car-following scenario and the extent of such benefits varies among tested human drivers owing to their intrinsic preferences and perception of CAV. These findings suggest that human-CAV interactions can be effectively leveraged to improve the energy efficiency of mixed traffic.

Researches on radar and infrared stealth compatibility have drawn much attention in recent years. In this work, a flexible metasurface with low infrared emission, broadband microwave absorption as well as high optical transmission is simultaneously achieved. The whole structure is composed of an infrared shielding layer (IRSL), a radar absorption layer (RAL), a substrate and a backplane, and the total thickness is only 3.5 mm. Based on the impedance matching theory, the microwave absorption higher than 90% can be achieved in the radar waveband ranging from 7.3 to 18.8 GHz, corresponding to a relative bandwidth of 88.1%. By using a conductive patch array as the IRSL, a low infrared emissivity of 0.49 can be realized in the infrared region from 8 to 14 μm. Moreover, by rational designing both the structures and materials, the metasurface in this work cannot only achieve bi-stealth functions with low infrared emission and broad microwave absorption, but also shows optically transparent and flexible properties, thus quite suitable for practical applications. Both the simulated and experimental results suggest that the proposed metasurface is promising in the multispectral stealth fields.

Construction of new enzyme reactor based on aptamer functionalized magnetic nanoparticles conjugated organic framework (COF) for acetylcholinesterase immobilization has been an enabling endeavor in this work. The aptamer against acetylcholinesterase was selected through a method based on capillary electrophoresis in one round. A new magnetic COF material rich of carboxyl groups was firstly synthesized, and its surface was then modified with the selected aptamer through covalently linking. Acetylcholinesterase was immobilized to fabricate the enzyme reactor Fe3O4@COF-Apt-AChE through the high affinity and specificity with its binding aptamer. The as constructed enzyme reactor was comprehensively characterized and the key factors that affected its catalysis efficiency were investigated in detail. Owing to the surface modification of the magnetic COF materials by aptamer for acetylcholinesterase immobilization, the immobilized enzyme exhibited improved substrates affinity. What's more, good reusability (more than 8 times) and prolonged stability (enzyme activity still kept at 90% after 42 days) were also achieved. Finally, the enzyme reactor could be applied in AChE inhibitors screening, which expanded its application capability. The proposed protocol not only paves a new way for fabrication of novel aptamer functionalized magnetic COF materials as enzyme reactors, but also indicates a broadened application of the integration of aptamer and its enzyme.

The degradation of inverted metamorphic four-junction (GaInP/GaAs/In0.3Ga0.7As/In0.58Ga0.42As, IMM4J) solar cells irradiated by 1-MeV electrons was investigated via their spectral responses and the characterization of their electrical properties. As in the case of traditional three-junction (TJ) GaInP/GaAs/Ge solar cells, the electrical properties ( I sc, V oc, and P max) decrease with the logarithmic change of the electron fluence. The degradation of open-circuit voltage ( V oc) is slightly more pronounced than that of I sc in IMM4J solar cells because of the sum rule for V oc and the limit rule for I sc. The spectral response analysis showed that an In0.3Ga0.7As subcell was the most damaged subcell in the irradiated IMM4J solar cell, but an In0.58Ga0.42As subcell had the lowest initial short-circuit current density (Jsc), which was maintained throughout the irradiation test. We therefore focused on the In0.58Ga0.42As subcell. Deep-level transient spectroscopy (DLTS) experiments were realized to study emission and capture processes in two special full configurations of In0.58Ga0.42As and In0.3Ga0.7As subcells of the IMM4J solar cell. DLTS measurements reveal a dominant electron trap at 0.52 eV below the conduction band (Ec) of In0.58Ga0.42As, and the electron trap gradually evolved into Ec-0.46eV and Ec-0.58eV after 1-MeV electron irradiation. Based on the first-principles calculation, Ec-0.46 eV and Ec-0.58 eV can be assigned as ${\bf V}_{{\bf Ga}}^{\bf 0}/{\bf V}_{{\bf Ga}}^{{\rm{ - }}1}$ and ${\bf V}_{{\bf In}}^{\bf 0}/{\bf V}_{{\bf In}}^{{\bf - 1}}$ , respectively. However, only one shallow level Ec-0.03eV was observed within the bandgap of In0.3Ga0.7As after irradiation with DLTS detection. We summarize the issues faced for the space application of IMM4J solar cells by comparing the spectral responses of IMM3J, IMM4J, and TJ solar cells. Finally, the optimization of the design and fabrication of IMM solar cells are proposed.

To assess the efficacy of the “Implementation Details of Air Pollution Prevention and Control Action Plan”, the chemical composition of PM2.5 and other pollutants was determined during the winters of 2013–2014 and 2016–2017 at two urban sites in Xiangtan City, Hunan. The concentrations of PM2.5, SO2, and NO2 decreased from 146.0 to 94.5 μg/m3, 75.9 to 33.5 μg/m3, and 80.6 to 55.8 μg/m3, respectively, from winter 2013–2014 to winter 2016–2017. The concentrations of almost all the major chemical components of PM2.5 decreased as well, particularly secondary inorganic aerosols (SIAs). These results indicate that the implementation of the air quality control plan was very effective in improving air quality. Analysis of the data also suggests that SIA formation is likely responsible for high winter PM2.5 pollution and that high relative humidity levels and low wind speed can promote the formation of SIA. A 72-h back trajectory analysis shows that both regional transport and the accumulation of local pollutants under stagnant meteorological conditions promote the occurrence of episodes of high wintertime pollution levels.

Gas atomization uses a high-speed gas flow to impact alloy melt and crush it into small droplets. During this process, the kinetic energy of the high-speed gas flow is transformed into the surface energy of small droplets, and the droplets are dragged and cooled by the gas. In this study, a FeNiCrBSiC alloy was used to investigate the motion and solidification behavior of alloy droplets during gas atomization. A mathematical model of the cooling and solidification process of droplets is modified and used. The initial velocity of the droplets attributed to the breakup by the high-speed gas flow is considered a factor. The results suggest that the velocity difference between the droplet and the gas is appearing to be smaller, indicating that droplets are more likely to collide with each other; as the velocity difference between the droplet and the gas becomes smaller, the heat transfer coefficient decreases. Thus, the solidification process of the droplet needs a longer flight distance; the relation between the cooling rate and the particle size was determined from measured data and empirical formula and model validation was performed.

In order to deeply understand the grain growth behaviors of Ni80A superalloy, a series of grain growth experiments were conducted at holding temperatures ranging from 1223 to 1423 K and holding time ranging from 0 to 3600 s. A back-propagation artificial neural network (BP-ANN) model and a Sellars model were solved based on the experimental data. The prediction and generalization capabilities of these two models were evaluated and compared on the basis of four statistical indicators. The results show that the solved BP-ANN model has better performance as it has higher correlation coefficient (r), lower average absolute relative error (AARE), lower absolute values of mean value (μ) and standard deviation (ω). Eventually, a response surface of average grain size to holding temperature and holding time is constructed based on the data expanded by the solved BP-ANN model, and the grain growth behaviors are described.

It is especially important to study on the change of 4H-SiC physical properties by swift heavy ion irradiation (SHI) for the future application of SiC devices in extreme irradiation environment. Herein, 4H-SiC Schottky barrier diodes (SBDs) are irradiated by 1.9 GeV 209Bi ion beams without intentional heating. The cross-sectional Micro-Raman Spectroscopy (MRS) results clearly indicated that there are new vibration bands at low fluence. This is attributed to the formation of homonuclear bonds Si–Si and C–C within the SiC network to break down the Raman selection rules. At high fluence, there are only typical Raman data for 4H-SiC crystal and the disappearance of Si–Si and C–C bonds. In addition, it is observed that the interfacial structure is modified due to the silicon and carbon atomic migration during SHI process at the metal-semiconductor interface, and then reacting at high temperature annealing treatment. Furthermore, these results suggest that the evolution of recrystallization effect is varied with irradiation fluence by the cross-sectional MRS.

A copper-catalyzed C(sp3)-H alkoxylation was developed to prepare quaternary α-alkoxylated amino acid derivatives in good yields. This protocol can be applied to a series of α-amino acids bearing a variety of functional group substituents. Facile removal of the auxiliary directing group and tolerance of condensation conditions for amide bond formation enable the potential application of this method in the discovery of new peptide drugs in the future.

Fluxapyroxad (Figure 1), a broad-spectrum pyrazole-carboxamide fungicide, is commonly employed for the treatment of a large variety of commercial crops. More specifically, the application of Fluxap...

In this work, we investigated the mixing of different constituent layers in an HfO2 dielectric oxide semiconductor by performing transmission electron microscope (TEM) characterizations. Energy dispersive X-ray (EDX) line scanning indicated that the elemental distribution extended into the substrates and the migration was bidirectional. The migration distance was at the same order of magnitude as the simulation result. The formation of new chemical bonds at the migration endpoint resulted in complex surface conditions. Hafnium oxide is considered a promising material for microelectronic devices with a size of less than 20 nm and has promising potential applications in aerospace engineering; therefore, the surface conditions determine the performance of the devices.

The privacy preserving Hamming distance problem of DNA sequences is defined and, by using a quantum commutative encryption scheme, a novel quantum protocol for solving it is proposed. A 0-1 coding scheme of DNA sequence is constructed, which transforms the privacy preserving Hamming distance problem of DNA sequences into privacy preserving Hamming distance problem of bit strings. Compared with other related protocols, the efficiency of the proposed protocol is improved, because of entanglement states, joint measurement, unitary operations and even Bell-state measurement are not needed, while only rotation operations and single-state measurement are required, which are easier to be realized with current technology. Furthermore, the correctness and security of the proposed protocol are also analyzed.

Hepatitis B virus (HBV) capsid assembly modulators (CAMs) have been suggested to be effective anti-HBV agents in both preclinical and clinical studies. In addition to blocking HBV replication, CAMs could reduce the formation of covalently closed circular DNA (cccDNA), which accounts for the persistence of HBV infection. Here, we describe the discovery of (1H-indazole-5-yl)sulfonamides and (1H-pyrazolo[3,4-c]pyridin-5-yl)sulfonamides as new CAM chemotypes by constraining the conformation of the sulfamoylbenzamide derivatives. Lead optimization resulted in compound 56 with an EC50 value of 0.034 μM and good metabolic stability in mouse liver microsomes. To increase the solubility, the amino acid prodrug (65) and its citric acid salt (67) were prepared. Compound 67 dose dependently inhibited HBV replication in a hydrodynamic injection-based mouse model of HBV infection, while 56 did not show in vivo anti-HBV activity, likely owing to its suboptimal solubility. This class of compounds may serve as a starting point to develop novel anti-HBV drugs.

The Jiaodong gold province, the largest gold producer in China, formed in a setting dominated by a 30-m.y. episode of Izanagi plate rollback and widespread extension, concomitant with late Mesozoic craton destruction. This study presents new high precision in situ sensitive high-resolution ion microprobe (SHRIMP) U-Th-Pb and laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) U-Pb ages for hydrothermal monazite from the largest of the Jiaodong gold deposits, which were previously dated as indicating ore formation over a few tens of millions of years when applying sericite Ar-Ar, zircon U-Pb, and less robust analytical techniques. Our U-Pb dating on monazite from the Jiaojia and Linglong deposits in western Jiaodong yielded consistent ages at ca. 120 Ma. The new geochronologic results, coupled with recently reported in situ monazite dates from smaller deposits in western Jiaodong, reveal that the deposits that host most of the ≥4,000-t Au resource formed during a relatively brief period at ca. 120 Ma. In eastern Jiaodong, the much smaller resource may have formed about 5 m.y. later, recorded by 114.2 ± 1.5 Ma gold mineralization at the Rushan deposit. The postsubduction opening of a slab gap at ca. 120 Ma is the most likely cause of the extensive gold mineralization in Jiaodong. The gap induced a local and rapid devolatilization of the hydrated mantle wedge at submelt temperatures. The transient event included release of a major volume of gold-transporting aqueous-carbonic fluid that was stored in the wedge into major NNE-trending structures in the overlying lithosphere.

A section from the Linglong gold deposit on the northwestern Jiaodong Peninsula, East China, containing Late Mesozoic magmatic rocks from mafic and intermediate dikes and felsic intrusions, was chosen to investigate the lithospheric evolution of the eastern North China Craton (NCC). Zircon U–Pb data showed that low-Mg adakitic monzogranites and granodiorite intrusions were emplaced during the Late Jurassic (~145 ​Ma) and late Early Cretaceous (112–107 ​Ma), respectively; high-Mg adakitic diorite and mafic dikes were also emplaced during the Early Cretaceous at ~139 ​Ma and ~118 ​Ma, and 125–145 ​Ma and 115–120 ​Ma, respectively. The geochemical data, including whole-rock major and trace element compositions and Sr–Nd–Pb isotopes, imply that the mafic dikes originated from the partial melting of a lithospheric mantle metasomatised through hydrous fluids from a subducted oceanic slab. Low-Mg adakitic monzogranites and granodiorite intrusions originated from the partial melting of the thickened lower crust of the NCC, while high-Mg adakitic diorite dikes originated from the mixing of mafic and felsic melts. Late Mesozoic magmatism showed that lithosphere-derived melts showed a similar source depth and that crust-derived felsic melts originated from the continuously thickened lower crust of the Jiaodong Peninsula from the Late Jurassic to Early Cretaceous. We infer that the lower crust of the eastern NCC was thickened through compression and subduction of the Palaeo-Pacific plate beneath the NCC during the Middle Jurassic. Slab rollback of the plate from ~160 ​Ma resulted in lithospheric thinning and accompanied Late Mesozoic magmatism. Keywords: Late mesozoic magmatism, Lithospheric thinning, Jiaodong peninsula, Eastern North China Craton

A mixed linker strategy has led to the discovery of the new metal–organic framework material, GT-18 (GT = Georgia Tech), which has no open metal sites and a chiral structure. The material includes ...

Downsizing copper nanoparticles (Cu NPs) can effectively improve their catalytic activity, but simultaneously ensuring the structural stability is always a challenge. In this study, by laser ablating a Cu target in graphene oxide (GO) solution along with a reduction treatment, pure Cu NPs (2.0 ± 0.4 nm) are evenly scattered on reduced graphene oxide (rGO). As-prepared Cu/rGO nanocomposites (NCs) are applied as catalysts for 4-nitrophenol (4-NP) reduction, which display high values of mass-normalized rate constant (k/m, 3.118 s−1 mgCu−1) and turnover frequency (TOF, 2.987 × 10−4 mmol mgCu−1 s−1), over those of most reported Cu catalysts. In addition, owing to the stable conjugation between ultrafine Cu NPs and rGO, the Cu/rGO catalysts reveal good catalytic stability that the conversion efficiency of 4-NP is still over 92.0% even after 10 successive cycles.

In this study, the capacitance-voltage (C-V) and current-voltage (I-V) characteristics of 4H-SiC Schottky barrier diode (SBD) irradiated by swift heavy ions (SHI) are studied under different ultraviolet (UV) conditions. The effective carrier concentration (ND), reverse current (IR), series resistance (RS), ideal factor (n) and Schottky barrier height (SBH) are calculated and analyzed. Furthermore, by analyzing the parameters, especially, ND, IR and n, a physical model is built. The UV illumination dependence of the recombination center states for defects or defect-states is presented.

Molecular studies on donkey mitochondrial sequences have clearly defined two distinct maternal lineages involved in domestication. However, domestication histories of these two lineages remain enigmatic. We therefore compared several population characteristics between these two lineages based on global sampling, which included 171 sequences obtained in this study (including Middle Asian, East Asian, and African samples) plus 536 published sequences (including European, Asian, and African samples). The two lineages were clearly separated from each other based on whole mitochondrial genomes and partial non-coding displacement loop (D-loop) sequences, respectively. The Clade I lineage experienced an increase in population size more than 8 000 years ago and shows a complex haplotype network. In contrast, the population size of the Clade II lineage has remained relatively constant, with a simpler haplotype network. Although the distribution of the two lineages was almost equal across the Eurasian mainland, they still presented discernible but complex geographic bias in most parts of Africa, which are known as their domestication sites. Donkeys from sub-Saharan Africa tended to descend from the Clade I lineage, whereas the Clade II lineage was dominant along the East and North coasts of Africa. Furthermore, the migration routes inferred from diversity decay suggested different expansion across China between the two lineages. Altogether, these differences indicated non-simultaneous domestication of the two lineages, which was possibly influenced by the response of pastoralists to the desertification of the Sahara and by the social expansion and trade of ancient humans in Northeast Africa, respectively.

The transmission and reflection properties of magnetostatic biased graphene layers are investigated based on analytical method, where graphene is treated as a bulk material. Considering the anisotropic nature of the magnetostatic biased graphene (magnetized graphene), the generalized reflection and transmission coefficients of a plane wave incidence on anisotropic multilayer structures are first derived. The accuracy of this method is validated by a numerical example of a plane wave incidence on a magnetized monolayer graphene in free space. Based on this model, the transmission coefficient decreases with increasing the incident angle for the TE (transverse electric) polarized wave incidence, while an opposite phenomenon occurs for the TM (transverse magnetic) polarized wave incidence. The transmission properties can be also modulated by changing the external static magnetic field. The electromagnetic propagation properties of composites consisting of magnetized graphene and dielectric layers are also analyzed based on this method. The transmission properties degrade with increasing the number of magnetized graphene layers.

Based on the first-order Taylor expansion, an efficient Rigorous Coupled-Wave Analysis (RCWA) for one-dimensional ultrathin periodic structures is proposed in this paper. The derivation of the ultrathin form RCWA method is completed by using the first-order Taylor expansion to rearrange the matrix in the equations of boundary conditions. Then, the reliability of the proposed algorithm is verified by two examples. Finally, it is concluded that the proposed algorithm can reduce the CPU time of TE polarization and TM polarization by more than 50%. Meanwhile, compared with the conventional algorithm, the proposed algorithm also needs less memory.

The Late Mesozoic tectonic evolution of the eastern North China Craton (NCC) remains controversial. In this study, a suite of Early Cretaceous mafic-intermediate dyke swarms found in the same secti...

Nanocomposites of graphene oxide/poly (diallyldimethyl ammonium chloride)/Ag nanoparticles (GO/PDDA/Ag NPs) were constructed via a self–assembly process as a surface-enhanced Raman scattering (SERS) substrate, in which functional macromolecules PDDA were utilized to load GO and support Ag NPs. Fundamental SERS performance of this SERS substrate was evaluated using rhodamine 6G (R6G), which displayed excellent enhancement effect, transferable nature and high stability of the synthesized GO/PDDA/Ag NPs substrate. Furthermore, the synthesized SERS substrate was employed in the sensitive detection of adenine with a linear range of 0.05–1000 μM and low detection limit of 1 nM. Other than the large surface area of GO, multiple-hydrogen bond interactions between adenine and the modified PDDA were another important factor in capturing adenine molecules and enhancing SERS signal. The hydrogen bond interaction was calculated using quantum mechanical calculations. Moreover, determination of adenine in aqueous solutions was achieved with good anti-interference ability against other nucleic bases with similar structures, such as guanine, cytosine and thymine. Therefore, GO/PDDA/Ag can be anticipated to be a potential substrate for label-free, fast and sensitive SERS detection of adenine in the field of bioanalysis.

Carbon molecular sieve (CMS) membranes are candidates for the separation of organic molecules due to their stability, ability to be scaled at practical form factors, and the avoidance of expensive supports or complex multi-step fabrication processes. A critical challenge is the creation of "mid-range" (e.g., 5-9 A) microstructures that allow for facile permeation of organic solvents and selection between similarly-sized guest molecules. Here, we create these microstructures via the pyrolysis of a microporous polymer (PIM-1) under low concentrations of hydrogen gas. The introduction of H2 inhibits aromatization of the decomposing polymer and ultimately results in the creation of a well-defined bimodal pore network that exhibits an ultramicropore size of 5.1 A. The H2 assisted CMS dense membranes show a dramatic increase in p-xylene ideal permeability (≈15 times), with little loss in p-xylene/o-xylene selectivity (18.8 vs. 25.0) when compared to PIM-1 membranes pyrolyzed under a pure argon atmosphere. This approach is successfully extended to hollow fiber membranes operating in organic solvent reverse osmosis mode, highlighting the potential of this approach to be translated from the laboratory to the field.

In this study, a well-dispersed Pd nanoparticle (NP)-supported RGO/Mn3O4 (G/M/Pd) composite was synthesized by a clean synthetic route, where galvanic replacement reaction simply occurred between Mn3O4 and a palladium salt, thereby avoiding the use of harsh reducing and capping agents. The G/M/Pd composite served as a robust catalyst for the catalytic oxidation of hydroquinone (HQ) to benzoquinone (BQ) with H2O2 in an aqueous solution. Oxidation was completed in only 4 min, with a turnover frequency (TOF) of 3613 h−1; this TOF is one hundred times those of previously reported Pd- and Ag-based catalysts. The superior performance was related to the electronic inductive effect between Mn3O4 and Pd NPs, which was verified by density functional theory calculations. Trapping experiments revealed that the oxidation of HQ was considerably related to the ·OH radicals generated from the decomposition of H2O2. In addition, the influencing factors were further investigated, including catalyst and HQ concentrations, solution pH, solvents, and various inorganic and organic interferences. Moreover, the G/M/Pd catalyst exhibits diverse applications for the catalytic oxidation of HQ derivatives with high TOFs.

Hydrothermal precipitates associated with active vents in the eastern Manus Basin, an actively opening back-arc basin in the Bismarck Sea, Papua New Guinea, are among the most Cu-rich on the modern seafloor. The volcanic rocks associated with this mineralization may be insufficiently enriched in Cu to account for the Cu content of the sulfides by simple leaching. The PACMANUS hydrothermal field lies in the eastern portion of the eastern Manus Basin. Mass balance modeling of the PACMANUS hydrothermal system indicates that simple leaching of a stationary reaction zone (0.144 km3) by hydrothermal fluids cannot yield the Cu found in associated sulfide deposits because unacceptably high leaching, transportation and precipitation efficiencies are required to derive the Cu in sulfides by leaching processes. With 100% leaching, transport and precipitating efficiency, 0.166 km3 of volcanic rocks would need to be leached to account for the Cu budget of hydrothermal sulfide deposits. The key requirement for forming metal-rich magmatic fluids is a large amount of metals available to enter the exsolved vapor phase. Magmas generated in the eastern Manus Basin inherently have high fO2 because of metasomatism of the mantle source by oxidized materials from the subducted slab, leading to copper enrichment in the magma chamber. Moreover, the presence of Cu in gas-rich melt inclusi on bubbles in Pual Ridge andesite is evidence that degassing and partitioning of Cu into the magmatic volatile phase has occurred in the eastern Manus Basin. Numerical mass balance modeling indicates that approximately 0.236 Mt Cu was potentially transferred to the hydrothermal system per cubic kilometer magma. Magmatic degassing seems to play a more significant role than leaching.

Taking Zn–Fe bimetallic organic-framework as both template and precursor, and furfuryl alcohol (FA) as secondary carbon source, a high-surface-area magnetic nanoporous carbon (MNPC) material was successful prepared. The MNPC exhibits excellent adsorption performance for bisphenol analogs (BPs). The maximum adsorption capacity achieved 439.0 mg g−1 for bisphenol AF, 423.7 mg g−1 for bisphenol S, 330.4 mg g−1 for tetrabromobisphenol A and 252.5 mg g−1 for bisphenol A. A sensitive magnetic solid-phase extraction with MNPC as adsorbent coupled with HPLC-UV analytical method was developed for the detection of trace BPs. The limits of detection for BPs were as low as 0.03–0.07 ng mg−1 with the RSDs of less than 4.6%. This method was applied to detection of four BPs in environmental water samples and the satisfactory results were obtained.

Based on the characteristics of inductance, resistance and capacitance of millimeter-sized metal single-turn (or multi-turn) coil, it is predicted that array formed by millimeter-sized metal coils with high-density distribution may hold near-zero permeability in a broadband of microwave frequency range. Simulations and experiments show that real part of relative permeability of ring-shaped array formed by copper coils is smaller than one and will decrease with the increase in either cross-sectional area or number of the coils; the imaginary part of the permeability remains small always, which is consistent with theoretical analysis. Our work may provide a convenient way to fabricate the broadband low-microwave-permeability metamaterials with low energy losses by using millimeter-sized single-turn (or multi-turn) coils.

Lysozyme is widely used in medical, food and industrial fields due to its bacteriolytic effect and thus it is significant to design and develop a specific adsorbent with high adsorption capacity and selectivity for lysozyme. Inspired by the high uptake capacity of tetrafluoroterephthalonitrile-crosslinked porous β-cyclodextrin polymers (P-CDPs) and the noncovalent interaction between lysozyme and carboxyl groups, the carboxyl-functionalized P-CDPs (P-CDP-COO−) were synthesized by base-catalysed hydrolysis of nitrile group in P-CDPs to carboxyl. Porous structure, large extent of carboxylic functional groups, cyclodextrin's preventing aggregation, and negatively charged make P-CDP-COO− possess an outstanding adsorption capability for lysozyme. The maximum saturated adsorption capacity reaches 1520 mg g−1, which is much better than the parent polymer and other reported materials. The as-prepared material was successfully utilized for the selective extraction of lysozyme from egg white.

Membrane-based organic solvent separations promise a low-energy alternative to traditional thermal separations but require materials that operate reliably in chemically aggressive environments. Whi...

Solid polymer electrolytes (SPEs) have the potential to enhance the safety and energy density of lithium batteries. However, poor interfacial contact between the lithium metal anode and SPE leads to high interfacial resistance and low specific capacity of the battery. In this work, we present a novel strategy to improve this solid-solid interface problem and maintain good interfacial contact during battery cycling by introducing an adaptive buffer layer (ABL) between the Li metal anode and SPE. The ABL consists of low molecular-weight polypropylene carbonate , poly(ethylene oxide) (PEO), and lithium salt. Rheological experiments indicate that ABL is viscoelastic and that it flows with a higher viscosity compared to PEO-only SPE. ABL also has higher ionic conductivity than PEO-only SPE. In the presence of ABL, the interface resistance of the Li/ABL/SPE/LiFePO4 battery only increased 20% after 150 cycles, whereas that of the battery without ABL increased by 117%. In addition, because ABL makes a good solid-solid interface contact between the Li metal anode and SPE, the battery with ABL delivered an initial discharge specific capacity of >110 mA·h/g, which is nearly twice that of the battery without ABL, which is 60 mA·h/g. Moreover, ABL is able to maintain electrode-electrolyte interfacial contact during battery cycling, which stabilizes the battery Coulombic efficiency.

Stress relaxation ageing behavior of pre-deformed AA2219 is studied through stress relaxation age experiments and finite element (FE) simulation. The results show that the stress can promote the process of ageing precipitation, and shorten the time to reach the peak strength. Meanwhile, the residual stress and yield strength increase along with the increase in the initial stress. Based on microstructure evolution and ageing strengthening theory, a unified constitutive model is established and incorporated into the FE simulation model through a user subroutine. It is found that the relative error of the radius is 3.6% compared with the experimental result and the springback is 16.8%. This indicates that the proposed stress relaxation ageing constitutive model provides a good prediction on the springback of such stiffened panel during its ageing process.

Analysis of glycans by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) is usually limited by the intrinsically low abundance and low ionization efficiency of glycans. Aiming to enhance the ionization efficiency of glycans and simplify the sample preparation procedure during MALDI-MS analysis, we reported herein a novel reactive matrix, 2-phenyl-3-(p-aminophenyl) acrylonitrile (PAPAN), for sensitive and selective detection of glycans. PAPAN is a derivative of α-cyanocinnamic acid, which possesses high ionization efficiency in MALDI-MS. The PAPAN can react with the terminal aldehyde of glycans and thereby enable the significant enhancement of ionization efficiency of glycans. As a result, using PAPAN as a reactive matrix, the detection sensitivity for glycans was improved 100-fold compared with that using 2,5-dihydroxybenzoic acid (DHB) as the matrix. Meanwhile, the ionization of peptides can be significantly suppressed using PAPAN as the matrix, which allowed the selective detection of N-glycans from a deglycosylated tryptic digest of glycoprotein without any prepurification. Moreover, the PAPAN matrix also endowed the analysis of glycans with enhanced fragmentation during MS/MS analysis, which could facilitate glycan structure interpretation. Finally, PAPAN was successfully used for the analysis of N-glycome in human serum. Thus, a simple, sensitive, and selective method for the analysis of glycans has been achieved by using a novel reactive matrix, PAPAN.

Gamma-ray radiation effects on the SiO2/HfO2/Al2O3/HfO2/Al2O3 based charge trapping memory have been investigated. Capacitance–voltage (C–V) and deep level transient spectroscopy (DLTS) measurements were applied to study the change in electrical properties from total dose radiation. C–V results showed a negative shift of flat-band voltage while dc memory window degraded after gamma-ray radiation. For DLTS result, two original peaks were found degraded while two new peaks appeared after radiation. Both C–V and DLTS results show that Gamma ray leads to the degradation of trapping effect.

The Early Cretaceous lithospheric mantle beneath the Jiaodong Peninsula has been recognized as ancient and enriched mantle with widespread mafic dike swarms. However, the enriching agent an...

A quantum protocol for millionaire problem based on commutative encryption is proposed. In our protocol, Alice and Bob don’t have to use the entangled character, joint measurement of quantum states. They encrypt their private information and privately get the result of their private information with the help of a third party (TP). Correctness analysis shows that the proposed protocol can be used to get the result of their private information correctly. The proposed protocol can also resist various attacks and overcomes the problem of information leakage with acceptable efficiency. In theory, our protocol can be used to build complex secure protocols for other multiparty computation problems and also have lots of other important applications in distributed networks.

A novel Mg2Si/Mg gradient composite was in-situ produced by electromagnetic directional solidification (EMDS). The microstructure of the composite changed longitudinally along with a primary Mg2Si-rich layer at the bottom and a Mg-rich eutectic layer at the top, respectively. The bio-corrosion behavior was investigated by electrochemical studies and static immersion tests. Both layers exhibited a much higher bio-corrosion resistance than high-pure Mg. Especially, the primary Mg2Si-rich phase revealed the greatest bio-corrosion resistance due to the corrosion blocking effect. Additionally, all the components originated from the gradient composite showed a good biocompatibility without obvious toxicity to osteoblasts. This work provided a new insight into the designing of gradient Mg2Si/Mg composite as a promising candidate for orthopedic implants.

A colorimetric assay is described for sensitive determination of Hg2+ ions based on the MoS2-Au composites as peroxidase mimetics, which are synthesized by microwave-assisted solvothermal method. The addition of Hg2+ stimulates their peroxidase-like activity, along with lower Michaelis constant toward the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) with H2O2, allowing the composites for direct determination of Hg2+. A broad linear response is obtained ranging from 20 nM to 20 μM with a detection limit (LOD) of 5 nM. The superior peroxidase-like activity is attributed to the large surface area of MoS2 nanosheets and the synergistic catalytic effect of MoS2 and Au. The Hg2+-stimulation effect implies the strong interaction between Hg2+ and MoS2-Au, where the XPS results confirm the presence of metallic Hg0, indicative of an Au-Hg amalgam. This colorimetric assay is successfully applied for the determination of Hg2+ in environmental water (tap water and Yellow River water) with excellent selectivity over interfering cations.

Two types of magnetically modified porous β-cyclodextrin polymers (PCDPs) were successfully synthesized. The first type, named MPCDPs(C), was fabricated by co-precipitating PCDPs with Fe3O4, resulting in a Brunauer–Emmett–Teller (BET) surface area of 106.68 m2 g−1. The second type, named MPCDPs(M), was fabricated by grafting PCDPs onto the surface of magnetic microspheres, resulting in a BET surface area of 34.63 m2 g−1. Both MPCDPs were found to enable effective extraction and separation of Sudan dyes from foodstuffs and environmental water. Coupled with high-performance liquid chromatography, the limits of detection for Sudan dyes were in the range of 0.013–0.054 ng mL−1 with MPCDPs(C), and 0.028–0.039 ng mL−1 with MPCDPs(M). Recoveries were between 85.8 and 102.8% for spiked food samples and 88.3 and 103.2% for spiked water samples, suggesting that the developed methods are promising for accurate quantification of Sudan dyes at trace levels in foodstuffs and environmental water.

It is an essential task for engineers to evaluate the residual strength of a fire-damaged steel structure, especially when collapse does not occur during the fire event. First of all, the mechanical properties of structural steels after fire were investigated through the experimental data. The stress–strain relationship model considering fire events was established. Then, the remaining load bearing capacity of a simple steel frame was evaluated using both the fiber and shell element numerical models. Finally, case study about the post-fire residual strength of a complex steel truss bridge was carried out. The results show that mechanical properties of the structural steels decrease after cooling down from an elevated temperature higher than $$500\, {^{\circ }}\hbox {C}$$ . Compared with the shell element model, the fiber element model is not able to predict accurately the post-fire inelastic behavior of a thin-walled steel structure. In most cases, the fire-exposed steel bridge still retains its original strength. However, it is apparently affected by the positions where the fire breaks out. The worst-case scenario is that the fire event occurs at the joint near the bearing supports, in which the strength decreases dramatically.

Developing multi-stimuli responsive fluorescent gel materials in a single system remains challenging. Gelator molecules with classical fluorophores suffer from the aggregation-caused quenching (ACQ) effect, limiting their applications further. Herein, a novel V-shaped cyanostilbene-based molecule (BAPBIA) with aggregation induced emission (AIE) characteristics and great gelation ability was synthesized and was found to exhibit multi-stimuli responsive behaviors. Reversible gel-sol phase transitions together with emission quenching are realized in response to external stimuli including heat, light and fluoride ions. Especially, the introduction of a dimethylaniline group (donor) and a cyano group (acceptor) generates a D-π-A structure, further leading to an intramolecular charge transfer (ICT) effect, which enlarges the emission contrast with the variation of the distribution of charge. Thus, upon trifluoroacetic acid (TFA) triggered protonation of the dimethylaniline group, not only a gel-sol transition but also emission color switching (yellow-to-blue) is achieved due to the loss of the ICT effect. This work paves an easy way to construct fully reversible multi-stimuli responsive fluorescence modulation smart materials.

This study investigates the release of NH3 and nitrogen oxides (NOx) from wastewater into the air in relation to the variations in NH3-N, NO2–-N, NO3–-N, and chemical oxygen demand (COD) concentrations in the swine wastewater with/without electrolysis using boron-doped diamond (BDD), PbO2, and graphite anodes. The NH3 concentration in the air right above the swine wastewater without electrolysis increased over time and this increase was greater when the wastewater NH3-N concentration was higher. Electrolysis could reduce the release of NH3 from swine wastewater into the air. The NO concentration in the air was greater for the wastewater without electrolysis than for that with electrolysis but an opposite trend was observed for NO2, although the corresponding NOx concentrations for the wastewater with and without electrolysis were similar. Roughly, the air NH3, NO, NO2, or NOx concentrations for using the different anodes in wastewater electrolysis followed the order Nb/BDD >> graphite/BDD > graphite > graphite/PbO2 ≈ Ti/PbO2. Although the BDD and graphite anodes showed less formation of nitrite or nitrate than the PbO2 anodes, the graphite/BDD and graphite anodes had worse performance in NH3-N or COD electro-degradation than the other tested ones. When the initial concentration of NH3-N or COD was higher, its specific energy consumption in electrolysis was lower.